El Nino pattern underway

NOAA scientists have announced the arrival of El Nino, a climate phenomenon with a significant influence on global weather, ocean conditions and marine fisheries.

El Nino, the periodic warming of central and eastern tropical Pacific waters, occurs on average every two to five years and typically lasts about 12 months.

NOAA expects this El Nino to continue developing during the next several months, with further strengthening possible. The event is expected to last through winter 2009-10.

El Nino Updates

Drought potential in for parts of the Ohio Valley

From mid-January through April 2010, the drought affecting California, Nevada, Arizona, and adjacent areas should continue to improve. Outlooks for late January and the February-April period call for enhanced chances of above-normal precipitation, except along the northern-most tiers of California and Nevada as well as adjacent southern Oregon, where more limited improvement is expected.

Farther north, drought is forecast to persist in central Washington and in areas near the Montana/Idaho border and should expand to cover the area between these two regions. Although odds favor a wet end to January in this region, drier than normal weather should prevail from February through April, consistent with conditions favored during El Niño episodes.

Farther east, some improvement can be expected in the recently-identified drought along and near the Idaho/Wyoming border, and in the protracted hydrologic drought affecting parts of the western Great Lakes region.

Elsewhere, most signs point to continued recovery for the residual drought areas in southern Texas, but existing short-term precipitation shortfalls and expected below-normal February – April precipitation should allow drought to develop in parts of northwestern Ohio by the end of the period.

U.S. Drought Monitor
Seasonal Drought Outlook (Map)